1. Field of the Invention
The present invention generally relates to optical units, and more particularly to an optical unit including photoelectric conversion modules and adapters for optical connectors.
An optical unit, after being inserted into and mounted in a shelf, is used with its optical connector adapters being connected with optical connectors provided to the ends of optical fiber cables that are external lines.
With an improvement in the performance of a semiconductor device included in the optical unit, an information processing rate per one optical unit has become higher and higher. For instance, the conventional rate of 1.2 Gbps is now doubled to 2.4 Gbps.
As the information processing rate of the optical unit increases, the number of channels that a single optical unit can handle also increases. Accordingly, the optical unit is allowed to increase the number of optical connectors connected to its optical connector adapters by increasing the number thereof.
2. Description of the Related Art
FIGS. 1A and 1B are diagrams showing a conventional optical unit 10. The optical unit 10 is of a single channel. The optical unit 10 includes optical connector adapters 11 and 12 on the front side (Y2 side in FIGS. 1A and 1B), photoelectric modules 13 and 14, a semiconductor device 15 for signal processing, and optical fibers 16 and 17 in the middle, and connectors 18 on the rear side (Y1 side in FIGS. 1A and 1B). The optical fibers 16 and 17 each have one end fixed to the photoelectric modules 13 and 14, respectively, with the middle parts being engaged with a reel. Optical connectors 20 and 21 provided to the other ends of the optical fibers 16 and 17 are inserted into the upper connection holes of the optical connector adapters 11 and 12, respectively, so as to be connected to the optical connector adapters 11 and 12.
The optical unit 10 is inserted and plugged into a shelf 30 with the connectors 18 being connected with connectors 32 provided on a back wiring board 31.
Optical connectors 42 and 43 provided to ends of optical fiber cables 40 and 41 that are external lines are inserted into the lower connection holes of the optical connector adapters 11 and 12, respectively, so as to be connected with optical connector adapters 11 and 12. Thereby, the optical fibers 16 and 17 are connected with the optical fiber cables 40 and 41, respectively.
The optical connector adapters 11 and 12 are attached to a lower part of an arm-like adapter attachment member 51 whose upper part is supported by a shaft 50.
Normally, the adapter attachment member 51 is at a vertical position as shown in FIG. 1A with the optical connector adapters 11 and 12 and the adapter attachment member 51 being accommodated in a narrow space 53 formed in the optical unit 10 on its front side.
When the optical connectors 42 and 43 provided to the ends of the optical fiber cables 40 and 41 are connected with or pulled out from the optical connector adapters 11 and 12, first, as shown in FIG. 1B, an operator pulls and turns the adapter attachment member 51 toward herself/himself (in the Y2 direction) with her/his fingers, and pulls the optical connector adapters 11 and 12 out of the space 53. Then, with the adapter attachment member 51 in this state, the operator performs connection or extraction of the optical fiber cables 40 and 41.
Since the two adapters 11 and 12 are pulled out together from the optical unit 10, a clearance a between the adapters 11 and 12 remains narrow outside the optical unit 10.
Therefore, even if levers for locking the optical connectors 42 and 43 to the adapters 11 and 12 were provided, it would be difficult to operate the levers. Accordingly, the optical connectors 42 and 43 are inserted into the adapters 11 and 12 so tight as to maintain connection by frictional force. Hence, if a strong pulling force is applied to the optical connectors 42 and 43, the optical connectors 42 and 43 may be pulled out from the adapters 11 and 12, thus questioning the reliability of the connection of the optical connectors 42 and 43 with the adapters 11 and 12.
In order to provide a lock mechanism, the clearance a between the adapters 11 and 12 is required to increase so that a finger of the operator may be allowed therein. This requires the space 53 to be considerably widened along the Y1-Y2 axis, thus causing the problem of increasing the optical unit 10 in size along the Y1-Y2 axis instead of downsizing the optical unit 10.
This problem is highlighted when the number of optical connector adapters is increased. Therefore, practically, it is not feasible to widen a clearance between adjacent optical connector adapters when the number of channels handled by a single optical unit is increased due to improvement in the information processing rate of a semiconductor device.
Accordingly, it is a general object of the present invention to provide an optical unit in which the above-described disadvantages are eliminated.
A more specific object of the present invention is to provide an optical unit whose reliability is increased without an increase in size.
The above objects of the present invention are achieved by an optical unit including photoelectric conversion modules, a plurality of adapter support members whose upper parts are rotatably supported, and a plurality of optical connector adapters attached to lower ends of the adapter support members so as to be arranged next to each other, the optical connector adapters being contained in the optical unit, wherein the adapter support members are rotated separately so that the optical connector adapters are extracted outside from the optical unit with a space formed between each adjacent two of the optical connector adapters, each of the optical connector adapters has insertion holes formed on each of first and second opposing sides thereof, optical connectors provided to ends of optical fibers extending from the photoelectric conversion modules are connected to the insertion holes formed on the first sides of the optical connector adapters, and optical connectors provided to ends of external optical fibers are connected to the insertion holes formed on the second sides of the optical connector adapters.
According to the above-described optical unit, the adapter support members are rotated independently so that the space, into which a finger is inserted for performing a connection operation, is formed between each adjacent two of the optical connector adapters. Accordingly, the optical unit permits usage of an optical connector with a lock lever, thus increasing the reliability of optical connector connections.